Objective: To evaluate the effect of massive weight loss on insulin sensitivity, soluble adhesion molecules, and markers of the insulin resistance syndrome (IRS).
Research methods and procedures: Eighteen morbidly obese patients underwent gastric banding and were evaluated before and 6 and 12 months after surgery. Total insulin secretion, hepatic insulin extraction, and insulin sensitivity were analyzed by oral glucose-tolerance test model analysis. In addition, soluble intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, leptin, high-sensitivity C-reactive protein, plasminogen activating factor-1 (PAI-1), and tissue plasminogen activator were measured.
Results: BMI dropped from 45.22 +/- 5.62 to 36.99 +/- 4.34 kg/m(2) after 6 months and 33.72 +/- 5.55 kg/m(2) after 12 months (both p < 0.0001). This intervention resulted in a significant reduction of blood pressure (p < 0.00001), triglycerides (p < 0.01), fasting blood glucose (p = 0.03), basal insulin (p < 0.001), and basal C-peptide (p = 0.008) levels. Total insulin secretion decreased (p < 0.05), whereas hepatic insulin extraction (p < 0.05) and oral glucose insulin sensitivity index (p < 0.0001) increased compared with baseline. Leptin (p < 0.0001) and E-selectin levels decreased significantly after 6 and 12 months (p = 0.05), whereas significantly lower levels of intercellular adhesion molecule-1 and PAI-1 were only seen after 6 months. Subclinical inflammation, measured by high-sensitivity C-reactive protein, was lowered to normal ranges. No changes were observed in vascular cell adhesion molecule-1 and tissue plasminogen activator levels.
Discussion: Although gastric banding ameliorates several features of the IRS, including 29.05% improvement in insulin sensitivity and blood pressure and reduction of soluble adhesion molecules and PAI-1, considerable weight loss did not normalize all components of the IRS in morbidly obese patients.